Secondary
Testing a leaf for starch
This procedure kills a leaf, disrupts the cell membranes and softens the cuticle and cell walls.
This makes it possible to extract the chlorophyll with hot ethanol and also allows the iodine
solution to penetrate the cells and react with any starch present.
http://www.practicalbiology.org/areas/introductory/energy/photosynthesis/testing-leaves-forstarch-the-technique,73,EXP.html
Secondary
How much energy is there in food?
Take samples of a range of foodstuffs and set them alight in turn. Burn food samples under a boiling
tube containing a measured amount of water. Measure the temperature increase in the water.
Calculate the amount of energy needed to cause that temperature increase. This gives an estimate
of the amount of energy stored in the food. The apparatus is very simple and the protocol gives only
a very approximate estimate for each foodstuff, so there is scope for students to suggest
improvements in an evaluation.
http://www.practicalbiology.org/areas/introductory/energy/energy-in-food/how-much-energy-is-there-infood,42,EXP.html
Secondary
Preserving food
Pupils investigate the effect of different preservatives on frozen peas in order to establish
that decay is caused by the action of microbes, and therefore preservatives work by reducing
microbe activity.
http://www.practicalbiology.org/areas/introductory/health-and-disease/preserving-food/preservingfood,96,EXP.html
Secondary
The causes of rusting
In this class experiment pupils put iron nails in various conditions including wet, dry, air-free
and salty to find out what causes iron to rust.
http://www.practicalchemistry.org/experiments/the-causes-of-rusting,209,EX.html
Secondary
Melting and freezing stearic acid
In this class practical pupils take the temperature of stearic acid at regular intervals as they
heat and cool it. They can observe melting and freezing points of the acid and can plot a
graph. This experiment would also be ideal done with data-logging equipment.
http://www.practicalchemistry.org/experiments/introductory/solids-liquids-and-gases/melting-and-freezingstearic-acid,191,EX.html
Secondary
Change in mass when magnesium burns
Magnesium is weighed and then heated in a crucible. It reacts with oxygen to produce the
oxide. It can be shown that there has been an increase in mass. The results can be used to
find the formula of magnesium oxide.
http://www.practicalchemistry.org/experiments/introductory/change/the-change-in-mass-when-magnesiumburns,207,EX.html
Secondary
Law of reflection
Class experiment showing that angle of incidence is equal to angle of reflection.
http://www.practicalphysics.org/go/Experiment_644.html?topic_id=2&collection_id=101
Secondary
Using ammeters
In this experiment pupils measure the current at various places in series and parallel circuits.
This provides an opportunity to introduce the ampere unit.
http://www.practicalphysics.org/go/Experiment_271.html?topic_id=8&collection_id=32
Secondary
Experiments with magnets
Magnets provide an introduction to attraction and repulsion, and to action at a distance.
Pupils investigate pairs of magnets, plotting compasses and iron filings.
http://www.practicalphysics.org/go/Experiment_189.html?topic_id=3&collection_id=26
Secondary
Reaction between carbon dioxide and
water
When carbon dioxide reacts with water a weak acid is formed. Carbon dioxide present in
exhaled air is blown into a flask containing an indicator sensitive to small changes of pH in
the appropriate region of the pH scale, and the consequent colour changes observed and
recorded. The equation for the reaction between carbon dioxide and water may be
introduced for appropriate students.
http://www.practicalchemistry.org/experiments/introductory/air-and-atmosphere/the-reaction-betweencarbon-dioxide-and-water,298,EX.html
Secondary
The Moon’s distance from Earth
An estimate of the ratio of the Moon’s distance from the Earth compared to its diameter. To
complete this experiment, hold a small coin just beyond arm's length and adjust its distance
from the eye until the disc of the coin just obscures the disc of the moon. A partner can then
measure the distance from the eye to the coin.
http://www.practicalphysics.org/go/Experiment_936.html?topic_id=43&collection_id=115
Secondary
Chemicals from seawater
This experiment is a simple one to carry out and is designed to show that seawater contains
a mixture of different salts. It can be used in conjunction with Earth Science topics linked to
the conveyance of mineral salts into the sea via rivers.
The seawater is heated gradually to precipitate solids.
http://www.practicalchemistry.org/experiments/introductory/the-earth/chemicals-fromseawater,195,EX.html
Secondary
Looking at a heart by dissection
It is possible to learn about the function of the heart from diagrams, models and animations.
However, the experience of dissecting real animal material adds an extra dimension to
understanding the structure of the heart and the relationship of structure to function. The
texture and thickness of vessel and chamber walls, and the movement of different kind of
valves are unforgettable.
http://www.practicalbiology.org/areas/intermediate/cells-to-systems/structure-of-a-heart/looking-at-aheart,76,EXP.html
Secondary
Effect of size on uptake by diffusion
Pupils set up cubes of agar jelly and see how far liquid penetrates them by diffusion over five
minutes. They calculate surface area to volume ratio for cubes of different sizes and consider
the problems faced by large organisms.
http://www.practicalbiology.org/areas/advanced/exchange-of-materials/diffusion/effect-of-size-on-uptakeby-diffusion,37,EXP.html
Secondary
Investigating the effect of caffeine on the
reaction time of a human reflex action
Pupils use a familiar protocol (dropping and catching a metre ruler) to investigate the effect
of drinking caffeinated drinks on their reaction times.
http://www.practicalbiology.org/areas/intermediate/control-and-communication/reflex-actions/measuringreaction-time-of-a-human-reflex-action,88,EXP.html
Secondary
Preparing a soluble salt by neutralisation
An acid and an alkali react to form a soluble salt in solution. Ammonia and sulfuric acid react
to form ammonium sulfate, which can then be recovered by crystallisation.
http://www.practicalchemistry.org/experiments/intermediate/acids-alkalis-and-salts/preparing-a-soluble-saltby-neutralisation,166,EX.html
Secondary
Alkali metals
A series of tests is carried out on the alkali metals, looking at their physical properties and
reactions with water. These demonstrations show the similarity of the physical and chemical
properties of the alkali metals and the trend in reactivity down Group 1 of the Periodic Table.
http://www.practicalchemistry.org/experiments/intermediate/periodic-table/alkali-metals,155,EX.html
Secondary
Identifying the products of electrolysis
This experiment enables pupils to carry out the electrolysis of various solutions (potassium
bromide, sodium iodide, zinc chloride…) and to investigate the identity of the products
formed at the electrodes. They should be able to link their practical experiences with theory
and learn how to construct simple ionic equations.
http://www.practicalchemistry.org/experiments/intermediate/electrolysis/identifying-the-products-ofelectrolysis,152,EX.html
Secondary
Ticker-timers for investigating speed
Making ticker-timer charts can develop an understanding of speed-time graphs.
One person should operate the ticker-timer switch while another walks away, pulling tape
through the ticker-timer. The walker should speed up and then slow down and stop, while
the tape is running through the timer.
http://www.practicalphysics.org/go/Experiment_266.html?topic_id=3&collection_id=31
Secondary
Simple electromagnet
An introductory experiment using a wire wrapped round an iron nail, which shows that
electromagnets can conveniently be switched on and off.
http://www.practicalphysics.org/go/Experiment_323.html?topic_id=7&collection_id=43
Secondary
Student power
Students measure their personal power by running up a flight of stairs.
http://www.practicalphysics.org/go/Experiment_511.html?topic_id=39&collection_id=74
Secondary
Earthquakes in the laboratory
Students design and build their own tower structures for testing, preferably tall and flimsy.
The towers are tested on a vibrating earthquake table.
http://www.practicalphysics.org/go/Experiment_244.html
Secondary
Water expands when it freezes
In this demonstration a bottle is filled with water and allowed to freeze. The water expands
as it freezes which breaks the bottle. This is useful when teaching about the weathering of
rocks and freeze-thaw.
http://www.practicalchemistry.org/experiments/introductory/the-earth/water-expands-when-itfreezes,190,EX.html
Secondary
Extracting metals with charcoal
In each of these two experiments, illustrating the idea of competition between metals and
carbon, students heat a metal oxide with powdered charcoal. If the carbon is more reactive
than the metal it will remove the oxygen from the metal oxide and leave traces of the metal
in the reaction vessel. The first experiment uses a lead(II) oxide; the second modifies the
technique slightly and uses a copper(II) oxide.
http://www.practicalchemistry.org/experiments/intermediate/metals/extracting-metals-withcharcoal,305,EX.html